A board with the profiles of various presidential candidates, amongst them Russia's current Prime Minister Vladimir Putin, is on display during the preparations for the upcoming presidential elections at a polling station in the southern Russian city of S

Russians have begun voting in the country's presidential election. Opinion polls say that Vladimir Putin is the lead candidate for a job that could keep him in the Kremlin through 2018.

Voting has started in a presidential election that is expected to give a six-year term to the leading candidate: Prime Minister Vladimir Putin.

Facing large opposition protests for the first time in his 12 years as Russia’s top leader, Mr. Putin campaigned hard in recent days, accusing Washington of funding his opponents and charging that the opposition is planning post-election violence. Further raising tension, Russian security services announced they had foiled a plot against his life.

As voting started in towns across the Bering Strait from Alaska, an army of over 200,000 volunteer poll watchers swung into action, hoping to reduce fraud. Another 600,000 Internet users have registered to monitor web cameras installed in all of Russia's nearly 100,000 polling stations. Mathematicians and voting experts calculate that fraud in the December 4 parliamentary elections boosted the ruling party’s winning tally by about 20 percent.

Since that vote, election officials have rejected almost all complaints and judges have ruled against almost all legal challenges. In addition, the Kremlin has fired four regional governors where the vote for the ruling party was below average.

In this environment, Russian protest organizer Natalia Pelevine predicts that fraud will also tarnish the presidential vote. "We see it as unfair. We really don't trust those in power to actually conduct proper, fair elections, and they haven't been up to this point, anyway, because there haven't been any serious debates among candidates; Putin certainly didn't participate in any," she said.

Mr. Putin said he was too busy to debate, but he did time find to meet Thursday night with foreign newspaper editors. At that meeting, he was vague when asked whether he plans to run for a second six-year term, a move that would put him at the top of Russian politics for a quarter-century.

David Satter, an American historian of Russia, says that many of his Russian friends fear that, with today’s vote, Russia will revert to its historical path, where leaders ruled from the Kremlin until their death. "Once Putin announced that he was running for president again, everyone started calculating how old they would be when he finally left office, if he leaves office. This sense of having a regime imposed on them, of having their rights taken away from them, this is something that has been a very powerful factor and has led to this spontaneous protest movement," he said.

Leaders of Russia’s street opposition predict that election officials will declare a Putin victory shortly after polls close Sunday. To fight back, they are organizing mass protests for Monday in Moscow and Russia's other biggest cities.

Olesya Shmagun, a 24-year-old Internet magazine editor, is serving as a volunteer election observer. As a voter, she plans to vote for Mikhail Prokhorov, the 2-meter-tall billionaire candidate who is winning the support of Russia’s discontented urban middle class. She hopes that if Prokhorov comes in second in Moscow and St. Petersburg, Mr. Putin will have to adopt some of Prokhorov's anti-corruption, pro-democracy platform.

But, hedging her bets, she also plans to go with friends to Monday’s opposition street rally in Moscow.

Referring to Sunday’s election, the opposition's protest slogan is: “March 4 is not the end, it is the beginning.”